Dtermination of tannins in rose water, wastewater and petal residue of Rosa damascena Mill

In this study, tannin was extracted from rose water, wastewater and petal residue of Rosa damascena Mill. Twenty one accessions collected from different provinces of Iran and cultivated in the Research Institute of Forests and Rangelands were sampled for extraction. Then, each sample of essential oil, rose water, wastewater and petal residue were prepared. The amount of tannin in the samples was measured by colorimetric method and spectrophotometer apparatus (Model 340 Hitachi) at 760 nm. The highest amount of tannin in rose water, wastewater and petal residue was respectively obtained from Khuzistan and Ilam (2163 ppm), Qom (1846 ppm), and Gillan (1432 ppm) accessions for rose water, Zanjan (1919 ppm), Mazandaran (1895 ppm) Qom, Gilan, Lorestan and Isfahan (1871 ppm) accessions for wastewater, and Yazd (3432 ppm), Sistan and Baluchestan (3139 ppm) and Kohgiluyeh-Boyer Ahmad (2993 ppm) accessions for petal residual. According to the results, it is recommended to extract tannin from samples used in rose water production. In other words, this will be economically useful for rose water traditional producers.